To the OP: If you're considering purchasing another enclosure for the snake at some point, I would urge you to check out reptile cages. These are not tanks but are display cages made specifically for reptiles. I get mine from Reptile Basics and I love them!! I live in the high desert of central Oregon where our typical humidity runs about 25-35% year round (dryer in the winter). It is not a struggle to keep the humidity between 50-60% with these cages.

I also have snakes in tubs, but, honestly, I would rather keep them in display cages with some sort of enriched environment for them. I figure since they run on instincts (basically) the least I can do for them is encourage the use of those instincts!

So, this is just really to put a bee in your bonnet, as it were!